After the death of his mother, the Tenma family became a father-son family with one parent and one child. - Her father worked tirelessly for her only daughter, and her daughter Yui was growing up seriously and quickly by watching her father's back, but Yui secretly had feelings for her father that were more than parent and child. - She comforted herself by masturbating every day to suppress such feelings, but one night when her father cut out the story of remarriage, Yui's desire that had accumulated in the pool finally exploded!